Logical Reasoning

PT107 · S1 · Q12 It is well known that many species

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It is well known that many species adapt to their environment, but it is usually assumed that only the most highly evolved species alter their environment in ways that aid their own survival.

Conclusion (However)

It's actually quite common for species to change the environment in ways that help their survival.

Evidence

The plankton is one example of a non-highly-evolved species that alters the environment for their own benefit.

They cool the earth by releasing a gas that ultimately facilitates cloud cover (and thus more sunlight reflecting back into space).

Evaluate

On Method, we're just trying to characterize the type of evidence or type of reasoning move used. There's about 8 of them that the test tends to go back to over and over again: analogy / (counter)example / implications of logic / ruling out other options / suggest alternate explanation / call out dubious assumption / raise an overlooked consideration

It seems like this would fall into the category of example / counterexample.

The author is trying to support a very general conclusion by means of a specific story about plankton (which is prefaced by "for example").

A generalization is usually assumed: only the most highly evolved species alter their environment in ways that aid their own survival

The author is offering a counterexample, a case in which a not-highly evolved species (plankton) alters its environment in ways that aid in its own survival.

Goal

Our standard on Method is simply, "If it matches, it's right." If it's descriptively true, take it. But we might assume we're probably going to hear something like, .

12.

Which one of the following accurately describes the argumentative strategy employed?

  1. A general principle is used

    Reversed Parts

    If we say X is used to justify Y, then X is the evidence and Y is the conclusion. Was the evidence here a "general principle? Was the conclusion "a particular case"? No, it's the other way around.

    13% picked this

  2. An explanation of how a

    Out of Scope: controversial phenomenon

    There's no controversial phenomenon that came about. Maybe people would think, "Since this goes against what is usually assumed, can we call it controversial?" Not really. But even if we did, we'd say the controversial phenomenon is "plankton (a non-highly evolved species) changing its environment to aid in its survival". Does the author offer an explanation of how plankton can change its environment to aid in its survival? Sure, the plankton generates a gas, which turns into sulfate, which causes water vapor to condense, which causes clouds, which reflects sunlight, which cools the Earth, which benefits the plankton. Does the author do this to support the conclusion that "this phenomenon did in fact come about"? No. The conclusion is not, "So you see, plankton really DID change their environment for their own benefit." The conclusion, instead, is "So you see, it's NOT just highly evolved species that change their environment for their own benefit."

    2% picked this

  3. A generalization about the conditions

    Weak Conclusion/Evidence Match

    Because this answer is structured, a generalization about X is advanced on the basis of Y that means X would be the conclusion and Y would be the evidence. Is the conclusion talking about "the conditions under which a certain process can occur"? Ugh. We could probably stretch that to match. A certain process [changing the environment to benefit your species' survival] can occur under conditions of [highly evolved species] as well as [not highly evolved species]. Does the evidence then examine certain cases in which that process did occur. No, it's just one case: plankton.

    17% picked this

  4. Correct

    A counterexample to a position

    Why this is right

    As we anticipated, this would fall into the (counter)example bucket. The position being challenged is that "only the most highly evolved species alter their environment in ways that aid their own survival". The author is saying, "No, that's incorrect. It's actually quite common for that to happen (even among not-most-highly evolved). Here's a counterexample for you: plankton do that thing you think is only true of the most highly evolved species."

    Skill tested: Method · how this choice captures the argument's function is the move to repeat next time.

    67% picked this

  5. A detailed example is used

    Out of Scope: strategy advantage

    They knew we'd fall in love with "a detailed example is used" and hoped we'd be too scared to get a divorce with the rest of the answer. A detailed example was used to illustrate that sometimes non-highly evolved species will also change their environment in ways that aid their survival. There is no discussion of any "strategies" and the author is certainly never endorsing one strategy as more advantageous than another.

    1% picked this

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